Daisy Chain issue

Technical discussions related to any XMOS development kit or reference design. Eg XK-1A, sliceKIT, etc.
JohnnyRoehn
Member
Posts: 15
Joined: Thu May 19, 2016 1:18 pm

Daisy Chain issue

Postby JohnnyRoehn » Tue Aug 09, 2016 10:23 am

Hello,

I am having an issue with the XMOS AVB Daisy Chain Kit when connecting to a talker stream. My setup consists of 4 Daisy Chain Boards connected in a daisy chain to a XMOS talker. When I try to connect one of the last 3 Boards in the daisy chain as a listener, they return a successful connection but there is no sound coming out of the analog outputs. Only If I then connect the first Daisy Chain board of the chain, all the others also output audio normally. After that I can also disconnect the first Daisy Chain board again and the other boards of the chain still can playout normally. It seems like the three other boards in the daisy chain need something like a sync once from the first daisy chain board to operate correctly.

Does anyone have the same problem or any solutions?
JohnnyRoehn
Member
Posts: 15
Joined: Thu May 19, 2016 1:18 pm

Postby JohnnyRoehn » Thu Sep 01, 2016 4:59 pm

No idea anyone?
User avatar
larry
Respected Member
Posts: 275
Joined: Fri Mar 12, 2010 6:03 pm

Postby larry » Fri Sep 02, 2016 2:17 pm

Which node is media clock source (LOCAL_CLOCK)?
JohnnyRoehn
Member
Posts: 15
Joined: Thu May 19, 2016 1:18 pm

Postby JohnnyRoehn » Mon Sep 05, 2016 9:36 pm

Do you mean the Grandmaster Clock of the AVB Network?
User avatar
larry
Respected Member
Posts: 275
Joined: Fri Mar 12, 2010 6:03 pm

Postby larry » Tue Sep 06, 2016 4:53 pm

One node runs its media clocks off a local clock source (the local PLL driven by XCore itself, based on XCore's system oscillator), this one prints "Setting clock source: LOCAL_CLOCK". All other nodes recover media clock (local PLL is driven by XCore based on incoming timestamps) for a given stream. They print "Setting clock source: INPUT_STREAM_DERIVED". If you have an LC endpoint alongside your DC boards, the LC will be media clock source. If there are multiple LCs, they will elect a source amongst themselves based on GUID (MAC address), see "simple demo controller".
JohnnyRoehn
Member
Posts: 15
Joined: Thu May 19, 2016 1:18 pm

Postby JohnnyRoehn » Mon Sep 19, 2016 2:18 pm

It seems like all of the devices show INPUT_STREAM_DERIVED on startup. I have one LC board and 4 DC boards in my setup. So what could be the problem?
User avatar
larry
Respected Member
Posts: 275
Joined: Fri Mar 12, 2010 6:03 pm

Postby larry » Mon Sep 26, 2016 4:28 pm

In AVB, one endpoint's media clock is locked to by all other endpoints. That way all endpoints can play synchronised audio.
JohnnyRoehn
Member
Posts: 15
Joined: Thu May 19, 2016 1:18 pm

Postby JohnnyRoehn » Tue Oct 04, 2016 9:04 am

Yes, I know that concept in AVB. I forgot that there is a Marvell Firefox AVB Switch between the 4 Daisy Chain Boards and the LC XMOS Talker. The Marvell Switch should be the Grandmaster Clock in this case. So could this clock be the problem?

Who is online

Users browsing this forum: No registered users and 4 guests